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Composites, technologies, equipment.

"Composite-Expo 2027" Exhibition
March 16 - 18, Pavilion 1, Halls 1 and 4, IEC Crocus-Expo, Moscow, Russia.

Website: composite-expo.com
Youtube: youtube.com/user/compositeexpo
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MIT researchers have developed a scalable fabrication technique for producing ultrathin, lightweight solar cells that can be stuck onto any surface.
Photo: Melanie Gonick, MIT.
Composites
MIT researchers have developed a scalable fabrication technique for producing ultrathin, lightweight solar cells that can be stuck onto any surface. Photo: Melanie Gonick, MIT.
Ultralight fabric solar cells can take charge of any surface

Engineers at Massachusetts Institute of Technology (MIT) have developed ultralight fabric solar cells that can quickly and easily turn any surface into a power source.

These durable, flexible solar cells, which are much thinner than a human hair, are glued to a strong, lightweight fabric, making them easy to install on a fixed surface. They can provide energy on the go as a wearable power fabric, or be transported and rapidly deployed in remote locations for assistance in emergencies. They are one-hundredth the weight of conventional solar panels, generate 18 times more power-per-kilogram, and are made from semiconducting inks using printing processes that can be scaled in the future to large-area manufacturing.

Because they are so thin and lightweight, these solar cells can be laminated onto many different surfaces. For instance, they could be integrated onto the sails of a boat to provide power while at sea, adhered onto tents and tarps that are deployed in disaster recovery operations, or applied onto the wings of drones to extend their flying range. This lightweight solar technology can be easily integrated into built environments with minimal installation needs.

“The metrics used to evaluate a new solar cell technology are typically limited to their power conversion efficiency and their cost in dollars-per-watt,” says Vladimir Bulovic, chair in emerging technology at MIT, leader of the Organic and Nanostructured Electronics Laboratory (ONE Lab), director of MIT.nano, and senior author of a paper on this work in Small Methods. “Just as important is integrability – the ease with which the new technology can be adapted. The lightweight solar fabrics enable integrability, providing impetus for the current work. We strive to accelerate solar adoption, given the present urgent need to deploy new carbon-free sources of energy.”

Traditional silicon solar cells are fragile, so they must be encased in glass and packaged in heavy, thick aluminum framing, which limits where and how they can be deployed. Six years ago, the ONE Lab team produced solar cells using an emerging class of thin-film materials that were so lightweight they could sit on top of a soap bubble. But these ultrathin solar cells were fabricated using complex, vacuum-based processes, which can be expensive and challenging to scale up.

In this work, the team set out to develop thin-film solar cells that are entirely printable, using ink-based materials and scalable fabrication techniques. To produce the solar cells, the engineers use nanomaterials that are in the form of a printable electronic ink. Working in the MIT.nano clean room, they coat the solar cell structure using a slot-die coater, which deposits layers of the electronic materials onto a prepared, releasable substrate that is only 3µm thick. Using screen printing (a technique similar to how designs are added to silkscreened T-shirts), an electrode is deposited on the structure to complete the solar module.

The researchers can then peel the printed module, which is about 15µm in thickness, off the plastic substrate, forming an ultralight solar device.

But such thin, freestanding solar modules are challenging to handle and can easily tear, which would make them difficult to deploy. To solve this challenge, the MIT team searched for a lightweight, flexible and high-strength substrate they could adhere the solar cells to. They identified fabrics as the optimal solution, as they provide mechanical resilience and flexibility with little added weight.

They ended up finding an ideal material — a composite fabric that weighs only 13 grams per square meter, commercially known as Dyneema. This fabric is made of fibers that are so strong they were used as ropes to lift the sunken cruise ship Costa Concordia from the bottom of the Mediterranean Sea. By adding a layer of UV-curable glue that is only a few microns thick, they adhere the solar modules to sheets of this fabric, forming an ultra-light and mechanically robust solar structure.
Photo Credit: Pusan National University
Composites
Photo Credit: Pusan National University
Pusan National University researchers introduce method to enhance thermally conductive composites

The proposed method has the potential to control the orientation of composite fillers without surface modification, improving thermal management.

In a new study at Pusan National University, Republic of Korea, Professor Chae Bin Kim and his team have developed a more energy-efficient method to control the orientation of fillers in thermally conductive polymer composites without the need for surface modification, resulting in improvement in thermal conductivity.

Owing to their lightweight nature and flexibility, thermally conductive polymer composites are applied between a heat source and a sink in electronics to dissipate the generated heat to the surroundings. Efficient heat dissipation is achieved due to the use of fillers with certain orientations that facilitate heat flow. The conventional process of modifying the orientation of the filler material, however, is an energy-intensive process that requires the use of electric/magnetic fields and surface modifications that can compromise the filler’s quality and its thermal properties.

The university researchers’ proposed method makes use of thermophoresis, a phenomenon in which a temperature gradient causes solid particles suspended in a fluid medium to move or rotate. To prepare the polymer composite, the researchers suspended thermally conductive hexagonal boron nitride (h-BN) filler particles in a UV-curable liquid and coated it between two glass plates. A temperature gradient was applied along the film thickness, causing the filler particles to rotate and realign along the applied temperature gradient. On achieving the desired orientations, the composite was photocured, resulting in a solid composite with fixed filler orientations that form a heat transfer pathway.

“To our best knowledge, the current study is the first experimental demonstration of controlling anisotropic filler orientation using thermophoresis,” Professor Kim says.
Thermally conductive polymer composites such as thermal paste are used in phones, laptops, even in batteries. Considering the growing production of electronics and the expected transition to electric vehicles (EVs), researchers contend that the proposed method has the potential to lower the energy cost of manufacturing thermally conductive polymer composites. Moreover, by avoiding the need for surface modifications, highly efficient thermally conductive polymer composites can be developed for improved heat dissipation and extend the life of electronics.

“Efficient heat dissipating materials can ensure best operating conditions for the device with improved reliability, lifespan and user’s safety,” Professor Kim adds.

Apart from improving thermal conductivity, fillers are also used to alter a composite’s optical, electrical and mechanical properties. By offering a way to reorient the filler without any surface modifications, the proposed method can also be adopted to tune the properties of a wide range of polymer composites without deteriorating their quality.
This research, “Thermally conductive 2D filler orientation control in polymer using thermophoresis” will be published in Volume 117 of Polymer Testing on Jan. 1, 2023.

#composites #PusanNationalUniversity #ConductiveComposites

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Composites
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ALUULA Composites selected for future NASA Mars missions

ALUULA Composites, a new advanced materials technology firm is pleased to report that its ultralight and strong composite materials have been selected by Thin Red Line Aerospace for future NASA missions.

ALUULA is supporting Thin Red Line Aerospace’s development of cutting edge, critical application hardware for future NASA lunar and Mars missions. “Their unique range of technical attributes combined with impressive strength to weight ratio specifications, make ALUULA Composite materials very well suited to the demanding requirements of technology in space.” Stated Thin Red Line Aerospace President, Maxim de Jong.

ALUULA Composites uses a patented fusion technology to bond films to a UHMWPE core, resulting in a new generation of performance composite fabrics that deliver unique and superior performance results. This “process, rather than a product” perspective allows for a wide range of iterations to meet a broad range of applications. “We continue to find new and exciting ways in which our process enables and enhances composite materials to satisfy very specific technical objectives, and our work with Thin Red Line is another great example of what is possible with our materials and unique expertise.” Said ALUULA Composites COO, John Zimmerman.

#composites #NASAMarsMissions #ALUULAComposites

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Researchers at Rice are pursuing the “sustainable valorization” of asphaltene by turning it into graphene useful for composite materials.
Illustration by M.A.S.R. Saadi
Composites
Researchers at Rice are pursuing the “sustainable valorization” of asphaltene by turning it into graphene useful for composite materials. Illustration by M.A.S.R. Saadi
Rice University turns asphaltene into graphene for composites

University scientists use novel flash Joule heating process to convert crude oil byproduct into graphene, to then be mixed with composites for thermal, anti-corrosion and 3D-printing applications.

Asphaltenes, a byproduct of crude oil production, are a waste material with potential, according to Rice University (Houston, Texas, U.S.) scientists. Muhammad Rahman, an assistant research professor of materials science and nanoengineering, is employing Rice’s novel flash Joule heating process to convert asphaltenes instantly into turbostratic (loosely aligned) graphene and mix it into composites for thermal, anti-corrosion and 3D-printing applications.

The process is said to make good use of material otherwise burned for reuse as fuel, or discarded into tailing ponds and landfills. Using at least some of the world’s reserve of more than one trillion barrels of asphaltene as a feedstock for graphene would be beneficial for the environment as well.

“Asphaltene is a big headache for the oil industry, and I think there will be a lot of interest in this,” says Rahman, who characterized the process as a scalable and sustainable way to reduce carbon emissions from burning asphaltene.

Rahman is a lead corresponding author of the paper in Science Advances co-led by Rice chemist James Tour, whose lab developed flash Joule heating, materials scientist Pulickel Ajayan and Md Golam Kibria, an assistant professor of chemical and petroleum engineering at the University of Calgary, Canada.

Asphaltenes are 70-80% carbon already, according to Rahman. The Rice lab combines it with about 20% carbon black to add conductivity and flashes it with a jolt of electricity, turning it into graphene in less than a second. Other elements in the feedstock, including hydrogen, nitrogen, oxygen and sulfur, are vented away as gases.

“We try to keep the carbon black content as low as possible because we want to maximize the utilization of asphaltene,” Rahman explains.

“The government has been putting pressure on the petroleum industries to take care of this,” Rice graduate student and co-lead author M.A.S.R. Saadi adds. “There are billions of barrels of asphaltene available, so we began working on this project primarily to see if we could make carbon fiber. That led us to think maybe we should try making graphene with flash Joule heating.”

Assured that Tour’s process worked as well on asphaltene as it did on various other feedstocks, including plastic, electronic waste, tires, coal fly ash and even car parts, the researchers set about making things with their graphene.

#composites #graphene #3Dprinting

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Photo Credit: Tuskegee University
Photo Credit: Reprinted from Composites Part C: Open Access, Vol 7, 2022, 100221, Zaheeruddin Mohammed, Shaik Jeelani, Vijaya Rangari, “Effective reinforcement of engineered sustainable biochar carbon for 3D printed polypropylene biocomposites”
Photo Credit: Reprinted from ACS Omega, Vol 7, 2022, 39636–39647, Zaheeruddin Mohammed, Shaik Jeelani, Vijaya Rangari, “Effect of Low-Temperature Plasma Treatment on Starch-Based Biochar and Its Reinforcement for Three-Dimensional Printed Polypropylene Biocomposites”
Composites
Photo Credit: Tuskegee University
New research developments identify new methods for bio-derived carbon filler reinforcement for biocomposites

Sustainable methodologies employed by researchers from Tuskegee University enable the synthesis of carbon from biomass-based precursor materials, and its effective reinforcement in composites.

Earlier in 2022, Zaheeruddin Mohammed, a graduate from the Department of Materials Science & Engineering at the Tuskegee University (Ala., U.S.), co-published new developments in more sustainable methodologies for effective biocomposite reinforcement. Specifically, the research details a method for making higher quality bio-derived carbon (called “biochar”) to be used to reinforce polymers in 3D printing applications.

Carbon-based nanomaterials such as fullerene, carbon nanotubes (CNTs), carbon nanofibers (CNFs), graphene nanoplatelets (GNPs) and carbon black are reinforcement filler materials that have been widely used to improve or enhance the mechanical properties of composite materials. However, they are traditionally derived from fossil fuel gases/liquids like methane, ethylene and acetylene, and require expensive and sophisticated processes to be manufactured [1].

Biochar, the synthesis of carbon from sustainable biomass-based precursor materials, is said to be a bio-based alternative to these more traditional carbon nanomaterials. In addition to a more sustainable and controlled processing method, biochar carbon still effectively enables excellent mechanical and thermal properties when used as a reinforcement filler; when it comes to thermoplastics in particular, it is noted that “biochar has a competitive advantage over other natural fillers, as they are more thermally stable to the heat induced during manufacturing processes like melt blending and extrusion [2].”

Nevertheless, current biochar is not as effective in improving mechanical and electrical properties of composites at low loading percentages as fossil fuel-based carbon nanomaterials; as a result high loading percentages of biochar carbons are required. To make biochar more competitive, researchers at the Tuskegee University synthesized high-quality biochar from sustainable starch-based packaging waste using a high-temperature/pressure pyrolysis reaction.

According to Mohammed et al, an ultrasonication method to reduce the particle sizes and increase active surface area was used, making biochar more compatible for dispersion, effective reinforcement and 3D printing. The modified biochar was used as an effective reinforcement filler with polypropylene polymer at a relatively low loading of 0–1 wt.%. In addition, tensile modulus and strength increased by 34% and 46% respectively with a loading of just 0.75 wt.%. Thermal stability of the composite material also improved by 51ºC in onset of decomposition temperature and 40ºC in maximum rate of decomposition temperature at 0.75 wt.%. Failure analysis of fractured surface revealed that ultrasonicated biochar was effective in reinforcing the material due to improved available surface area and nanosize defects formed on the surface of biochar carbon.

The next challenge was achieving a good interface between the filler and the matrix. Instead of traditional wet methods for surface modification, Mohammed and his team employed low-temperature plasma (LTP) treatments in the presence of sulfur hexafluoride (SF6) gas. Ultimately, the technology was effective in the fluorination of biochar carbon like in wet chemical methods, improving tensile strength by 91% when compared to neat polymers and 31% compared to untreated biochar-reinforced polymers at 0.75 wt.% loadings. Elongation at break also increased from 12.7 to 38.78, showing a 216% increase. In this work, it was shown that plasma-based treatments were an effective and sustainable path to develop composite parts using additive manufacturing methods with improved mechanical and thermal properties [3].

#composites #biocomposites

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The official website of the Composite-Expo 2023 Exhibition contains the exhibitor's manual in PDF and Word formats.

In it you can find answers to all frequently asked questions, as well as get acquainted in detail with the nuances of the days of mounting / dismantling of stands, the arrival of vehicles on the territory of the Expocentre Fairgrounds and other working moments.

> go to the exhibition website
Toray and its partners’ in-situ VARTM technique.
Photo Credit: Toray Industries Inc.
Composites
Toray and its partners’ in-situ VARTM technique. Photo Credit: Toray Industries Inc.
Toray jointly wins Infrastructure Maintenance award for steel pipe repair innovation

Together with Tokyo Electric Power Grid and Yasuda Seisakusho, Toray employed in-situ VARTM with carbon fiber sheets to repair steel pipe corrosion on transmission towers, with application extension underway.

Toray Industries Inc. (Tokyo, Japan) was one of three joint recipients to receive a Minister of Economy, Trade and Industry Award in the “Electricity” category for Japan’s sixth Infrastructure Maintenance Awards. Recognition goes to the development of a carbon fiber-reinforced plastic (CFRP) technique employing in-situ vacuum-assisted resin transfer molding (VARTM) technology. Toray, Tokyo Electric Power Grid Inc. (Japan) and Yasuda Seisakusho Co. Ltd. (Tokoyo) used the technique to repair steel pipe corrosion on transmission towers.

The innovation eliminates the need for special jigs and methods in replacement work by reinforcing pitted and corroded pipes, thus also reducing lead times for strength assessments and cutting construction costs. Another key factor in receiving this award was the broad social benefits that could accrue from applying this technology to steel-framed buildings and other structures.

The patented in-situ VARTM technology entails placing carbon fiber sheets — Torayca carbon fiber fabric — on a steel structure requiring repair. A film is applied over the composite sheets, and a pump is used to create a vacuum to injection and cure the epoxy resin.

Applications to date for this technology include transmission towers in Japan and floating production storage and offloading facilities overseas. Work is underway to extend applications to repair and reinforce steel bridges, steel-framed buildings and other structures.

#composites #Toray #CarbonFiberSheets #repair

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Vestas unveils circularity solution to end landfill for turbine blades

A novel chemical process, developed within the CETEC initiative with partners Olin and Stena Recycling, is capable of breaking down epoxy resin to virgin-grade material.

Vestas Wind Systems A/S (Aarhus, Denmark) is presenting a new solution that renders epoxy-based wind turbine blades as circular, without the need for changing the design or composition of the blade material. Combining newly discovered chemical technology developed within the CETEC initiative, and partnerships with Olin (Clayton, Mo., U.S.) and Stena Recycling (Frogner, Norway), the solution can be applied to blades currently in operation. Once matured, Vestas says this will eliminate the need for blade redesign, or landfill disposal of epoxy-based blades when they are decommissioned.

“Until now, the wind industry has believed that turbine blade material calls for a new approach to design and manufacture to be either recyclable, or beyond this, circular, at end of life,” Lisa Ekstrand, vice president and head of sustainability at Vestas, says. “Going forward, we can now view old epoxy-based blades as a source of raw material. Once this new technology is implemented at scale, legacy blade material currently sitting in landfill, as well as blade material in active wind farms, can be disassembled, and reused. This signals a new era for the wind industry, and accelerates our journey towards achieving circularity.”

Turbine blades have previously been challenging to recycle due to the chemical properties of epoxy resin, a resilient substance that was believed to be impossible to break down into reusable components. This has led to many technology leaders attempting to replace or modify epoxy resin with alternatives that can be more easily treated. Vestas’ solution is enabled by a novel chemical process that can chemically break down epoxy resin into virgin-grade materials. The chemical process was developed in collaboration with Aarhus University (Denmark), Danish Technological Institute (Taastrup) and Olin the partners of the CETEC project, a coalition of industry and academia established to investigate circular technology for turbine blades.

“The newly discovered chemical process shows that epoxy-based turbine blades, whether in operation or sitting in landfill, can be turned into a source of raw material to potentially build new turbine blades,” Mie Elholm Birkbak, specialist, innovation and concepts at Vestas, adds. “As the chemical process relies on widely available chemicals, it is highly compatible for industrialization, and can therefore be scaled up quickly.”
WindEurope expects around 25,000 tonnes of blades to reach the end of their operational life annually by 2025.
Through a newly established value chain, supported by Nordic recycling company Stena Recycling and global epoxy manufacturer Olin, Vestas will now focus on scaling up the novel chemical disassembly process into a commercial solution. Once mature, the solution will signal the beginning of a circular economy for all existing and future epoxy-based turbine blades.

Read: Moving toward next-generation wind blade recycling

For several decades, producing wind turbine blades manufactured with epoxy-based resin has been standard practice in the wind industry. In the most mature markets for wind energy, the first turbines are reaching the end of their operational life and this will increase over the coming years.

In addition, the new solution will provide Vestas with the opportunity to produce new turbine blades made from reused blade material. In the future, the new solution also signals the possibility to make all epoxy-based composite material a source of raw material for a broader circular economy, potentially encompassing industries beyond wind energy.

#composites #Toray #CarbonFiberSheets #repair

Photo Credit: Getty Images

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Toray and Takagi Seiko Corp. (Toyama, Japan) molded this large model member with a CFRF core and a CFRP skin.
Photo Credit: Toray Industries Inc.
Composites
Toray and Takagi Seiko Corp. (Toyama, Japan) molded this large model member with a CFRF core and a CFRP skin. Photo Credit: Toray Industries Inc.
Toray develops rapid integrated press molding technology for CFRP mobility components

The process and material innovation simultaneously shapes, molds, thermosets and bonds the core and skin in the same mold, achieving this 10 times faster than conventional autoclave molding setups.

Toray Industries Inc. (Tokyo, Japan) has developed a rapid integrated press molding technology for carbon fiber-reinforced plastic (CFRP) mobility components.
This material sandwiches a light, porous short carbon fiber-reinforced foam (CFRF) core (fibers 5-10 millimeters long) with a specially formulated fast cure-type thermoset prepreg.

A combination of process- and material-based innovation, the technology reportedly makes it possible to press mold such components — a car roof, for example — 10 times faster than a conventional autoclave molding setup. Toray obtained findings for this technological advancement under the New Energy and Industrial Technology Development Organization’s (NEDO) Research and Development of Innovative Structural Materials project.

CFRP members typically sandwich urethane foam cores with thermoset prepreg skins. Common applications for these light and rigid structures are large panels for aircraft, automobiles, ships and infrastructure. Some manufacturers have pushed for shorter manufacturing times to optimally bond the core after shaping it to the skin.
Toray confirmed that the skin-core interface did not delaminate and that impact absorption is excellent.

Toray’s new rapid integrated molding technology makes it possible to fabricate large panels in a single shot. Through heat and pressure, the approach simultaneously shapes, thermosets and molds, and bonds the core and skin in the same mold. Ultimately, synchronizing CFRF’s expansion with the prepreg’s curing timing is significantly faster than with conventional processes, Toray reports. The prepreg’s thermoset resin penetrates the porous CFRF to bond the skin and core materials without using adhesives, for a highly reliable bonding structure. Toray’s technology may pave the way for quick production of large CFRP components.

According to the company, CFRF offers significantly better strength, elastic modulus and impact resistance than conventional core materials. Its low specific gravity range of 0.2 to 0.4 can enhance performance and lighten sandwich structures. Toray demonstrated its concept by using a pressing machine to create a large automotive roof panel (1.2 meters long, 1.2 meters wide and 2.3 millimeters thick) in just five minutes. Core thickness before molding was 1.7 millimeters, and 0.8 millimeter after molding. The company assessed rigidity, coatability, sound insulation properties and other practical aspects for automotive production. In vital drop-weight impact tests, Toray confirmed that the skin-core interface did not delaminate and that impact absorption is excellent.

Read: Plant tour: Avel Robotics, Lorient, France

Generally, Toray says it is looking to replace any panel component that its technology can be applied to, taking advantage of the innovation’s ability to create lightweight parts with high rigidity that also excel in impulsivity, sound and heat insulation.

Toray says it will keep pursuing R&D to accelerate the application of this technology to electrified vehicle parts, for which lightness and fast production are vital. The company also looks to cultivate such emerging transportation modalities as urban air mobility (UAM) and drones that benefit from functional, lightweight materials.

The technology is still in its development stage, but the company aims to commercialize it by 2030, offering a materials-based technology and a process-based

#composites #Toray #CFRP

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